Methods for placement of vascular stents and vascular stents

ABSTRACT

The present invention provides a vascular stent graft. The vascular stent graft comprises a main vessel stent graft and a bypass stent graft to bypass a portion of vascular anatomy, connecting branch stent graft to provide flow to branch vessels to remove a portion of the vascular anatomy from circulation. The main vessel stent graft is designed with or punctured to contain an access port through which the bypass or connecting branch stent graft is received. A sealing relationship is formed between the stents to prevent leakage or bleeding.

CLAIM OF PRIORITY UNDER 35 U.S.C. §§ 119 AND 120

The present application for patent is a Continuation in Part and claims priority to patent application Ser. No. 10/643,554 entitled “VASCULAR STENT GRAFTS” filed Aug. 18, 2003, pending, which is hereby expressly incorporated by reference herein, which claims priority to Provisional Patent Applications Nos. 60/404,343 and 60/404,344, filed Aug. 19, 2002, entitled “MODULAR RECONSTRUCTABLE ENDOVASCULAR BYPASS STENT GRAFT” and “MODULAR RECONSTRUCTABLE STENT GRAFT” which are hereby expressly incorporated by reference herein.

REFERENCE TO CO-PENDING APPLICATIONS FOR PATENT

None.

BACKGROUND

1. Field

The technology of the present application relates to vascular surgery and, more particularly, vascular stent grafts useful in bypassing or removing portions of vascular anatomy from circulation and/or reconstructing vascular anatomy.

2. Background

The circulatory system comprises many different parts, one of which is the vascular system. Blood vessels can develop various problems, diseases, or other pathology that frequently requires surgical repair.

Two common conditions include vascular blockage, such as, for example, blood clots, and aneurysms. Blockage is generally repaired surgically by, for example, bypass surgery, a balloon catheter, or the like. Surgeons conventionally treat aneurysms by surgically removing the aneurysm. Some aneurysms can be treated using endovascular methodologies including placing a graft, but frequently endovascular treatment is not possible because branch vessels become occluded. But, these and other conventional procedures for correcting vascular pathology are not particularly satisfactory. Thus, it would be desirous to develop apparatuses that allowed for endovascular repair of the vascular system.

SUMMARY

To attain the advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, methods to facilitate endovascular repair of a diseased vessel are provided. In particular, the method comprises locating a main vessel of the endovascular system that requires repair. Making a single incision to allow access to the main vessel. Placing a branch stent in a branch vessel located off of a main vessel. Locating a main vessel stent in the main vessel such that the branch stent is occluded. Puncturing a wall of the main vessel and providing a branch connecting stent from the main vessel stent to the branch stent such that the main vessel stent and the branch stent are in fluid communication thereof.

The foregoing and other features, utilities, and advantages of the technology of the present application will be apparent from the following more particular description of exemplary embodiments as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the technology of the present application, and together with the descriptions, serve to explain the principles thereof. Like items in the drawings may be referred to using the same numerical reference.

FIG. 1 shows a portion of a vascular anatomy with an endovascular stent graft consistent with the technology of the present application;

FIG. 2 shows devices useful for placement of the endovascular stent graft of FIG. 1;

FIG. 3 shows puncturing a main vessel stent graft consistent with establishing a working port;

FIG. 4 shows a cross-sectional view of an access port and bypass stent graft consistent with an embodiment of the technology of the present application;

FIG. 5 shows a portion of a vascular anatomy with an endovascular stent graft consistent with another embodiment of the technology of the present application;

FIG. 6 shows puncturing a main vessel stent graft consistent with establishing a working port;

FIG. 7 shows a portion of a vascular anatomy with an endovascular stent graft consistent with another embodiment of the technology of the present application;

FIG. 8 shows another construction of main vessel stent graft 508; and

FIG. 9 shows an illustrative flow chart describing a method of implanting stents consistent with the technology of the present application.

DETAILED DESCRIPTION

Some embodiments of the present invention are described with reference to FIGS. 1 to 9. The embodiments are described with reference to exemplary embodiments thereof. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. Moreover, unless otherwise stated, all embodiments described herein should be construed as exemplary.

Referring first to FIG. 1, a cut-away portion of a blood vessel 100 is shown. A clot 102, blockage, or other vascular pathology in blood vessel 100 requires a bypass. An endovascular bypass stent 104 is shown implanted in vessel 100. Endovascular bypass stent 104 comprises a main vessel stent graft 106 and a bypass stent graft 108. Main vessel stent graft 106 has an access port 110 located proximate clot 102. Bypass stent graft 108 has a proximate end 112 and a distal end 114. Proximate end 112 is connected to access port 110 in a sealing relationship, which will be explained further below with respect to FIG. 4. Distal end 114 resides within vessel 100 such that bypass catheter 108 bypasses clot 102 or other vascular pathology.

Implanting or deploying endovascular bypass stent 104 will be explained with reference to FIG. 2. First a main deployment catheter 202 and main vessel stent graft 106 are guided to clot 102 using standard endovascular surgical techniques. Main deployment catheter 202 comprises a proximate balloon 204, a distal balloon 206, and a working port 208. Inflating proximate balloon 204 and distal balloon 206 isolates working port 208 from blood flow.

Referring now to FIG. 3, a trocar 302 is passed through the main deployment catheter 202 and out working port 208 once balloons 204 and 206 isolate blood flow. Using 3-D navigational technology (as is commonly available in the art), trocar 302 is aligned with working port 208 and used to puncture vessel 100 about working port 208. As shown in FIG. 3, main vessel stent graft 106 may be deployed without a working port. In this case, trocar 302 first punctures main vessel stent graft 106 to make the working port. When the working port in main vessel stent graft 106 is made by trocar 302, main vessel stent graft 106 is designed to form a controlled tear pattern, such as a controlled stellate pattern 304, as is commonly known in the art.

Once vessel 100 is punctured, a bypass catheter 210 is passed to the vascular pathology. Bypass catheter 210 comprises a dissecting balloon 212 and a tool port 214 at the distal end thereof. A wire needle 216 is passed out tool port 214. Using the bypass catheter 210, dissecting balloon 212 passes through the puncture and enters the perivascular space about vessel 100. The dissecting balloon dissects the perivascular space up to a vessel re-entry port 218. Vessel re-entry port 218 is shown as a part of blood vessel 100 such that clot 102 is removed from circulation, but vessel re-entry port 218 could reside in a separate blood vessel (not specifically shown) as required by the patient's anatomy and the particular pathology involved. Wire needle 216 punctures the vessel to establish re-entry port 218.

Once wire needle 216 establishes re-entry port 218, bypass catheter 210 is removed and bypass stent graft 108 is passed over wire needle 216. Distal end 114 is placed in the vessel at re-entry port 218 and expanded to fit snuggly with the vessel wall in a sealing relationship. Bypass stent graft could be expanded using a balloon or made out of an expanding material, such as, for example, shaped memory alloys. The proximate end 112 and access port 110 are joined in a sealing relationship, as explained below.

Once bypass stent graft 108 is placed, proximate balloon 204 is deflated and blood flow is verified. Finally, distal balloon 206 is deflated and the catheter is removed leaving endovascular bypass stent 104 in place.

FIG. 4 shows the sealing relationship between access port 110 and proximate end 112 in more detail. In particular, a cross-sectional view of access port 110 and proximate end 112 is shown. Access port 110 has an edge 402 defining access port 110. About edge 402 is a seating surface 404. Proximate end 404 has a corresponding engaging surface 406. Engaging surface 406 mates with seating surface 404 to form a seal that inhibits blood leakage. Reference number 408 is a material that further inhibits bleeding. Reference number 408 could be a sealing ring, such as a GORTEX® washer, that could be deployed between seating surface 404 and engaging surface 406 to further inhibit blood flow. Alternatively, reference number 408 could be a form of epoxy, acrylic, silicone, tape, glue, or resin that seals seating surface 404 and engaging surface 406. Still further, bypass stent graft 108 and/or main vessel stent graft 102 could be constructed out of shaped memory alloys, such as, for example, Ag—Cd alloys, Cu—Al—Ni alloys, Cu—Sn alloys, Cu—Zn alloys, Cu—Zn—Si alloys, Cu—Zn—Sn alloys, Cu—Zn—Al alloys, In—Ti alloys, Ni—Al alloys, Ni—Ti alloys, Fe—Pt alloys, Mn—Cu alloys, Fe—Mn—Si alloys, and the like. These could be designed such that seating surface 404 and engaging surface 406 form an adequate seal and then deformed for deployment. After deployment, an activation signal could cause seating surface 404 and engaging surface 406 to join in a sealing relationship. The activation signal could be a thermal, electrical, magnetic, radiation signal or the like. Notice, the seal between access port 110 and bypass stent graft 108 could be accomplished using a connecting stent. Connecting stents are explained further below with reference to FIG. 7.

Referring now to FIG. 5, another embodiment of the present invention is shown. FIG. 5 shows a cut-away portion of a vessel 500. In this case, vessel 500 contains a type of aneurysm 502 or other vascular pathology that needs to be isolated from vessel 500. As shown, vessel 500 has branch vessels 504 that prevents the use of a conventional stent because a conventional stent would occlude blood flow to branch vessels 504 indefinitely. In this case, endovascular stent graft 506 includes a main vessel stent graft 508 and a number of branch connecting stent grafts 510. In this case, two branch connecting stent grafts 510 are shown, but more or less could be deployed as necessitated by patient anatomy. Branch connecting stent grafts 510 pass through access ports 512 in main vessel stent graft 508 such that a distal 514 of branch connecting stent graft 510 resides in branch vessels 504 and a proximate end 516 of branch connecting stent graft 510 is in a sealing relationship with access port 512, such sealing relationship is further explained above in connection with FIG. 4.

Endovascular stent graft 506 can be deployed in a number of different ways. For example, main vessel stent graft 508 can be placed using conventional endovascular techniques. Once placed, using 3-D surgical navigation techniques, commonly known in the art, a trocar 602 is used to puncture main vessel stent graft 508 at the junction with branch vessel 504 (See FIG. 6). Main vessel stent graft 508 is constructed such that trocar 602 would from a controlled tear 604, such as a controlled stellate pattern. A balloon 606 would be used to dilate tear 604 to a size capable of accepting branch connecting stent graft 510. Branch connecting stent graft 510 is the passed to the site such that distal end 514 resides in branch vessel 504 and proximate end 516 forms a sealing relationship with access port 512.

While main vessel stent graft 508 (and main vessel stent graft 106) is shown as a tubular member conforming to the shape of the vessel 500 (or 100), main vessel stent graft 508 could be other shapes, such as, for example, a y shaped main vessel stent graft 800. In this case, y branch 802 would replace branch connecting stent 510 y (FIG. 5). Other shapes are possible.

Alternatively to using 3-D surgical navigation, FIG. 7 shows placing branch locating stent graft 702. Branch locating stent graft 702 would have a radiopaque edge 704 proximate vessel 500. Main vessel stent graft 508 would be passed to the vascular site occluding branch vessels 504. Trocar 604 would then be aligned with radio opaque edge 704 and main vessel stent graft 508 would be punctured to form access port 512. A connecting stent 706 would then be placed such that a distal end 708 of connecting stent 706 resided in and formed a sealing relationship with branch locating stent 702 and a proximate end 710 of connecting stent 706 resides in and forms a sealing relationship with access port 712.

Referring now to FIG. 9, a flowchart 900 is provided illustrating an exemplary methodology associated with one or more of the stents described above. First, a surgeon would locate or identify a portion of the vascular system that required repair or removal from blood flow, step 902. For example, vessel 500 has aneurysm 502, see FIG. 5, or the like is identified by the surgeon. Next, a single incision is made in the endovascular system to provide surgical access to the vessel, step 904. For example, an incision 550 may be made in vessel 500, see FIG. 5. Using conventional surgical techniques, such as, for example, inserting a catheter through incision 550 to branch vessels, branch stents or branch locating stents 702 are placed in branch vessels 504. Branch stents may be provided with radio opaque edges 704, step 906. Main vessel stent 506 is placed, step 908, following placement of branch vessel stents 702 using conventional surgical techniques. Main vessel stent 506 occludes branch stents 702. A trocar, or the like, punctures the wall of main vessel stent 506 to provide an access port on the wall, step 910. A branch connecting stent 706 is then provided to provide fluid communication between main vessel stent 506 and branch stents 702, step 912. Subsequently, the tools are removed and the incision closed, step 914. Optionally, the trocar can be located using surgical navigation equipment to locate the radio opaque edges, step 909.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. 

1. A method for the repair of a diseased vessel comprising the steps of: locating a vessel of the endovascular system that requires repair or removal from blood flow; making a single incision into the endovascular system to provide access to the located vessel; placing a branch stent in one or more branch vessels branching from the located vessel; placing a main vessel stent in the located vessel temporarily occluding the branch stent; puncturing a wall of the main vessel stent to provide an access port from the main vessel stent to the branch stent; and placing a branch connecting stent such that the main vessel stent and the branch stent are in fluid communication.
 2. The method of claim 1, wherein the branch stent includes a radio opaque edge and the method further comprises locating the radio opaque edge and wherein the puncturing a wall step comprises puncturing the wall at the located radio opaque edge.
 3. The method of claim 1, further comprising tearing the wall of the main vessel stent in a controlled pattern to form the access port.
 4. The method of claim 1, wherein the access port includes an edge and a seating surface about the edge and the method further comprises expanding the branch connecting stent to form a sealing relationship with the seating surface.
 5. A vascular stent graft for removing a portion of vascular anatomy from circulation but preserving circulation to branch vessels, the vascular stent graft comprising: a main vessel stent graft, the main vessel stent graft having a punturable wall, the main vessel stent graft to provide a flow path through an aneurysm of a vessel and being pucturable after placement to provide at least one access port on a wall adapted to be aligned with a corresponding number of branch vessels in the aneurysm; at least one branch stent graft adapted to be placed in the branch vessel prior to placement of the main vessel stent graft; an occlusion residing between the main vessel stent graft and the at least one branch stent graft after placement of the main vessel stent graft and prior to placement of the at least one branch connecting stent graft; means for puncturing the main vessel stent graft to remove the occlusion; and at least one branch connecting stent graft, wherein each of the at least one branch connecting stent grafts received in a corresponding one of the at least one access port on the wall of the main vessel stent graft such that a distal end of the branch connecting stent graft is adapted to reside in a branch vessel in a sealing relationship with the at least one branch stent graft and a proximate end of the branch connecting stent graft forms a sealing relationship with the access port and the branch connecting stent provides a flow path through the aneurysm and wherein the branch vessel is occluded prior to puncturing the main vessel graft stent.
 6. The vascular stent graft of claim 5, wherein the means for puncturing comprises a trocar.
 7. The vascular stent graft of claim 5, wherein the access port on the wall of the main vessel stent graft is formed by puncturing the wall of the main vessel stent graft and expanding the puncture in a controlled pattern.
 8. The vascular stent graft according to claim 5, wherein the access port is defined by an edge and a seating surface resides about the edge, and the proximate end of the branch connecting stent graft comprising an engaging surface, such that when the branch connecting stent graft is received by the access port, the seating surface and engaging surface form the sealing relationship.
 9. The vascular stent graft according to claim 5, wherein the at least one branch connecting stent graft comprises a plurality of branch connecting stent grafts.
 10. The vascular stent graft according to claim 8, wherein at least the proximate end of the branch connecting stent graft comprises an expandable material such that the proximate end is expanded until the engaging surface and the seating surface form a sealing relationship.
 11. The vascular stent graft according to claim 10, wherein the proximate end of the branch connecting stent graft is flared.
 12. The vascular stent graft according to claim 10, wherein each of the at least one branch stents comprises a radio opaque edge.
 13. The vascular stent graft according to claim 12, wherein the means for puncturing punctures the main vessel at a location identified by the radio opaque edge.
 14. A vascular stent graft for removing a portion of vascular anatomy from circulation but preserving circulation to branch vessels, the vascular stent graft comprising: one or more branch stent graft adapted to be placed in a branch vessel a main vessel stent graft to provide a flow path through an aneurysm of a vessel having a wall designed for puncturing, the main vessel stent graft adapted to temporarily occluding the branch vessel; means for puncturing the main vessel stent graft to provide an access port in the wall between the main vessel stent graft and the one or more branch vessel stent graft such that the branch vessel is not occluded by the main vessel stent graft; and one or more branch connecting stent grafts corresponding to the one or more branch stent grafts, wherein each of the at least one branch connecting stent grafts received in a corresponding one of the at least one access port on the wall of the main vessel stent graft such that a distal end of the branch connecting stent graft is adapted to reside in a branch vessel in a sealing relationship with the at least one branch stent graft and a proximate end of the branch connecting stent graft forms a sealing relationship with the access port and the branch connecting stent provides a flow path through the aneurysm and wherein the branch vessel is occluded prior to puncturing the main vessel graft stent.
 15. The vascular stent graft of according to claim 14, wherein the means for puncturing is a trocar. 